diff --git a/src/main/java/org/gcube/informationsystem/discovery/knowledge/AddElementToTreeAction.java b/src/main/java/org/gcube/informationsystem/discovery/model/knowledge/AddElementToTreeAction.java
similarity index 96%
rename from src/main/java/org/gcube/informationsystem/discovery/knowledge/AddElementToTreeAction.java
rename to src/main/java/org/gcube/informationsystem/discovery/model/knowledge/AddElementToTreeAction.java
index 4f98e17..0635ef4 100644
--- a/src/main/java/org/gcube/informationsystem/discovery/knowledge/AddElementToTreeAction.java
+++ b/src/main/java/org/gcube/informationsystem/discovery/model/knowledge/AddElementToTreeAction.java
@@ -1,7 +1,7 @@
 /**
  * 
  */
-package org.gcube.informationsystem.discovery.knowledge;
+package org.gcube.informationsystem.discovery.model.knowledge;
 
 import org.gcube.informationsystem.base.reference.Element;
 import org.gcube.informationsystem.discovery.DiscoveredElementAction;
diff --git a/src/main/java/org/gcube/informationsystem/discovery/knowledge/ClassInformation.java b/src/main/java/org/gcube/informationsystem/discovery/model/knowledge/ClassInformation.java
similarity index 93%
rename from src/main/java/org/gcube/informationsystem/discovery/knowledge/ClassInformation.java
rename to src/main/java/org/gcube/informationsystem/discovery/model/knowledge/ClassInformation.java
index 04b32f3..73499ce 100644
--- a/src/main/java/org/gcube/informationsystem/discovery/knowledge/ClassInformation.java
+++ b/src/main/java/org/gcube/informationsystem/discovery/model/knowledge/ClassInformation.java
@@ -1,4 +1,4 @@
-package org.gcube.informationsystem.discovery.knowledge;
+package org.gcube.informationsystem.discovery.model.knowledge;
 
 import java.util.LinkedHashSet;
 import java.util.Set;
diff --git a/src/main/java/org/gcube/informationsystem/discovery/knowledge/Knowledge.java b/src/main/java/org/gcube/informationsystem/discovery/model/knowledge/Knowledge.java
similarity index 98%
rename from src/main/java/org/gcube/informationsystem/discovery/knowledge/Knowledge.java
rename to src/main/java/org/gcube/informationsystem/discovery/model/knowledge/Knowledge.java
index 1fab69a..52d9d14 100644
--- a/src/main/java/org/gcube/informationsystem/discovery/knowledge/Knowledge.java
+++ b/src/main/java/org/gcube/informationsystem/discovery/model/knowledge/Knowledge.java
@@ -1,4 +1,4 @@
-package org.gcube.informationsystem.discovery.knowledge;
+package org.gcube.informationsystem.discovery.model.knowledge;
 
 import java.util.LinkedHashMap;
 import java.util.Map;
diff --git a/src/main/java/org/gcube/informationsystem/discovery/knowledge/ModelKnowledge.java b/src/main/java/org/gcube/informationsystem/discovery/model/knowledge/ModelKnowledge.java
similarity index 98%
rename from src/main/java/org/gcube/informationsystem/discovery/knowledge/ModelKnowledge.java
rename to src/main/java/org/gcube/informationsystem/discovery/model/knowledge/ModelKnowledge.java
index f1ef74e..2177d26 100644
--- a/src/main/java/org/gcube/informationsystem/discovery/knowledge/ModelKnowledge.java
+++ b/src/main/java/org/gcube/informationsystem/discovery/model/knowledge/ModelKnowledge.java
@@ -1,4 +1,4 @@
-package org.gcube.informationsystem.discovery.knowledge;
+package org.gcube.informationsystem.discovery.model.knowledge;
 
 import java.util.Collection;
 import java.util.HashMap;
diff --git a/src/main/java/org/gcube/informationsystem/discovery/knowledge/ModelKnowledgeValidator.java b/src/main/java/org/gcube/informationsystem/discovery/model/knowledge/ModelKnowledgeValidator.java
similarity index 97%
rename from src/main/java/org/gcube/informationsystem/discovery/knowledge/ModelKnowledgeValidator.java
rename to src/main/java/org/gcube/informationsystem/discovery/model/knowledge/ModelKnowledgeValidator.java
index 08374fb..6601e8f 100644
--- a/src/main/java/org/gcube/informationsystem/discovery/knowledge/ModelKnowledgeValidator.java
+++ b/src/main/java/org/gcube/informationsystem/discovery/model/knowledge/ModelKnowledgeValidator.java
@@ -1,7 +1,7 @@
 /**
  * 
  */
-package org.gcube.informationsystem.discovery.knowledge;
+package org.gcube.informationsystem.discovery.model.knowledge;
 
 import java.util.ArrayList;
 import java.util.Collection;
diff --git a/src/main/java/org/gcube/informationsystem/discovery/knowledge/UsageKnowledge.java b/src/main/java/org/gcube/informationsystem/discovery/model/knowledge/UsageKnowledge.java
similarity index 95%
rename from src/main/java/org/gcube/informationsystem/discovery/knowledge/UsageKnowledge.java
rename to src/main/java/org/gcube/informationsystem/discovery/model/knowledge/UsageKnowledge.java
index a9d7a14..ade083f 100644
--- a/src/main/java/org/gcube/informationsystem/discovery/knowledge/UsageKnowledge.java
+++ b/src/main/java/org/gcube/informationsystem/discovery/model/knowledge/UsageKnowledge.java
@@ -1,4 +1,4 @@
-package org.gcube.informationsystem.discovery.knowledge;
+package org.gcube.informationsystem.discovery.model.knowledge;
 
 import java.util.Collection;
 import java.util.LinkedHashMap;
diff --git a/src/main/java/org/gcube/informationsystem/serialization/ElementMapper.java b/src/main/java/org/gcube/informationsystem/serialization/ElementMapper.java
index b3f4f24..56cbe34 100644
--- a/src/main/java/org/gcube/informationsystem/serialization/ElementMapper.java
+++ b/src/main/java/org/gcube/informationsystem/serialization/ElementMapper.java
@@ -30,7 +30,7 @@ import org.gcube.com.fasterxml.jackson.databind.node.TextNode;
 import org.gcube.informationsystem.base.reference.AccessType;
 import org.gcube.informationsystem.base.reference.Element;
 import org.gcube.informationsystem.discovery.Discovery;
-import org.gcube.informationsystem.discovery.knowledge.Knowledge;
+import org.gcube.informationsystem.discovery.model.knowledge.Knowledge;
 import org.gcube.informationsystem.model.reference.ModelElement;
 import org.gcube.informationsystem.types.TypeMapper;
 import org.gcube.informationsystem.types.reference.Type;
diff --git a/src/test/java/org/gcube/informationsystem/discovery/DiscoveryTest.java b/src/test/java/org/gcube/informationsystem/discovery/DiscoveryTest.java
index b944809..14f8c2d 100644
--- a/src/test/java/org/gcube/informationsystem/discovery/DiscoveryTest.java
+++ b/src/test/java/org/gcube/informationsystem/discovery/DiscoveryTest.java
@@ -4,8 +4,8 @@ import java.util.Map;
 
 import org.gcube.informationsystem.base.reference.AccessType;
 import org.gcube.informationsystem.base.reference.Element;
-import org.gcube.informationsystem.discovery.knowledge.Knowledge;
-import org.gcube.informationsystem.discovery.knowledge.ModelKnowledge;
+import org.gcube.informationsystem.discovery.model.knowledge.Knowledge;
+import org.gcube.informationsystem.discovery.model.knowledge.ModelKnowledge;
 import org.gcube.informationsystem.tree.Tree;
 import org.gcube.informationsystem.types.TypeMapper;
 import org.gcube.informationsystem.types.reference.Type;